The present invention relates to a paste formulation, a tool, and a system for root canal treatment, and more particularly relates to the paste used for root canal filling, a paste injector, and a system used therewith.
In dental clinical treatments, root canal treatments are popularly operated. Among the root canal treatments, root canal filling is operated at the final stage of the root canal treatment, and then the root canal filling has large effects on prognosis of a damaged tooth. Since the length to an apical constriction varies from individual patients, a length of the root canal must be measured. A method for this measurement includes, conventionally to measure an actual length of the tooth by using a reamer, a file, or a scale as detection probes for an x-ray photograph. Recently, a method for measurement of the root canal length using an impedance is widely used, because there is a case that the x-ray exposure is not adequate for a pregnant woman and the impedance measurement is speedy and provides exact results.
The root canal length measurement by impedance conventionally uses a root canal meter. A working length is then determined to be the reamer length inserted in the root canal minus 1 mm which is indicated by a predetermined impedance previously measured depending on the conditions of the instruments for measurement when a top of the reamer contacts the periodontal membrane. Alternatively, the working length is determined as the length that gives current or resistance being different by a certain value from the value which indicates contact to the periodontal membrane.
A root canal filling material, or root canal filling agent such as a filler paste formulation conventionally used for the root canal filling includes a gutta percha point used together with various sealers, silver points and a filler in a paste formulation which may be formulated with a sustainable disinfectant or an accelerator for healing with osteoid scar.
Especially, a method for filling the paste formulation in the root canal portion includes filling the paste formulation through the reverse-rotated reamer operated by hand, filling by using a filling device with a helical shape such as Rentulo plugger, or filling the paste through a paste injector. However, the methods using the reamer and Rentulo plugger have disadvantages, because these methods require an extra procedure for measuring the root canal length and the special device.
FIG. 9 shows a conventional method for filling the paste formulation into the root canal by the injector. In the conventional root canal filling method using the injector, the injector 1 shown in FIG. 9(a) filled with the paste formulation M is used. The injector 1 comprises a container portion 2 and an insert portion 3 which may be inserted into the container portion 2. A tube for injection of the filler is disposed at a front end of the container portion 2 to form an injection portion 4. In FIG. 9(a), the tip of the paste injection tube is inserted into the root canal portion which has previously been spread widely.
In the conventional root canal filling method, as shown in FIG. 9(b), the paste formulation M is injected into the root canal while inserting the filler injection tube into the root canal and pressing the insert portion 3 in the direction of the arrow A. When the filling is completed, the filler injection tube is drawn out from the root canal and then the root canal filling operation is completed.
When the root canal is filled by the injector, as described above, an advantage to complete the injection easily and quickly may be provided without the procedure to measure the root canal length previously. However, this method has some disadvantages, that is, filling of the paste to the apical constriction is unknown and the paste formulation may irritate root peripheral tissues when the paste formulation is injected beyond the apical constriction. When the filling is not enough, a dead space and/or residual pulps may be allowed to exist. Therefore, there are needs for the paste formulation, the paste injector, and the system for detecting the paste filling.
In the first aspect of the present invention, a paste formulation for dental use comprising electric conductive material may be provided.
In the first aspect of the present invention, the paste formulation is provided, wherein the electric conductive material is powder.
In the first aspect of the present invention, the paste formulation for dental use may be provided, wherein the electric conductive material is selected from the group consisting of metal powder, metal oxide powder, coated inorganic powder by metal and/or doped metal oxide, carbon powder, carbon whiskers, and whiskers integrated with metal.
In the first aspect of the present invention, the paste formulation for dental use may be provided, wherein the paste formulation includes at least one compound selected from the group consisted of calcium hydroxide, hydroxy apatite, tricalcium phosphate.
In the first aspect of the present invention, the paste formulation for dental use may be provided, wherein the paste formulation includes at least one compound selected from the group consisting of iodoform, barium sulfate, anhydrous zinc sulfate, aluminum sulfate, and zinc oxide.
In the first aspect of the present invention, the paste formulation for dental use may be provided, wherein the paste formulation includes at least one vehicle selected from the group consisting of silicone oil, guaiacol formaldehyde mixture, propylene glycol, dry ethanol, caster oil, liquid paraffin.
In the first aspect of the present invention, the paste formulation for dental use may be provided, wherein the paste formulation includes at least one compound selected from the group consisting of iodoform, barium sulfate, anhydrous zinc sulfate, aluminum sulfate, and at least one vehicle selected from the group consisting of silicone oil, guaiacol-formaldehyde mixture, propylene glycol, dry ethanol, caster oil, and fluid paraffin.
In the first aspect of the present invention, the paste formulation for dental use may be provided, wherein the paste formulation includes an x-ray contrast agent.
In the first aspect of the present invention, the paste formulation for dental use may be provided, wherein the electric conductive material is present between 5xcx9c50 wt % based on a solid of the paste formulation.
In the first aspect of the present invention, the paste formulation for dental use may be provided, wherein the paste formulation includes at least one compound selected from the group consisting of calcium hydroxide, hydroxy apatite, tricalcium phosphate not less than 30 wt % based on a solid of the paste.
In the second aspect of the present invention, a paste injector may be provided. The paste injector comprises;
a container portion within which electric conductive paste is held,
an insert portion inserted into the container portion,
an injection portion for injecting the electric conductive paste formulation into a constricted portion, and
an electric conductive member for electrically connecting the electrically conductive paste formulation to an external electrode.
In the second aspect of the present invention, the paste injector may be provided, wherein the electric conductive member comprises a terminal exposed at an end face of the insert portion inserted into the paste container portion and contacting the electric conductive paste formulation, a terminal disposed at the insert portion and exposed outside the insert portion, and a lead line connecting between the terminals.
In the second aspect of the present invention, the paste injector may be provided, wherein the electric conductive member is inserted through the insert portion.
In the second aspect of the present invention, the paste injector may be provided, wherein the electric conductive member comprises an end extending through an inner path of the injection portion, an end drawn out of the paste injector, and a lead line connecting between the ends.
In the third aspect of the present invention, a system for detecting paste filling may be provided. The system comprises;
a paste injector comprising an electric conductive paste formulation and an electric conductive member for electrically connecting the electric conductive paste to an external electrode,
a current detector for detecting the current flowing through the electric conductive paste formulation injected into a constricted portion, and
a current display device for indicating the current flowing through the electronic conductive paste.